# Solving Vibronic Dynamics in Electron Continuum

## TL;DR

The paper introduces a model for studying electron-molecule collisions involving metastable states and compares methods for solving resonance dynamics.

## Contribution

A novel two-dimensional model of conical intersections and comparison of Krylov-subspace solvers for electron continuum dynamics.

## Key findings

- Two Krylov-subspace methods with different preconditioning were compared for resonance dynamics.
- One method was successfully applied to a CO2 vibrational excitation model with four vibrational degrees of freedom.
- Electron energy-loss spectra from the models were analyzed to assess scattering outcomes.

## Abstract

We present a general two-dimensional model of conical
intersection
between metastable states that are vibronically coupled not only directly
but also indirectly through a virtual electron in the autodetachment
continuum. This model is used as a test ground for the design and
comparison of iterative solvers for resonance dynamics in low-energy
electron–molecule collisions. Two Krylov-subspace methods with
various preconditioning schemes are compared. To demonstrate the applicability
of the proposed methods on even larger models, we also test the performance
of one of the methods on a recent model of vibrational excitation
of CO2 by electron impact based on three vibronically coupled
discrete states in continuum (Renner–Teller doublet of shape
resonances coupled to a sigma virtual state) including four vibrational
degrees of freedom. Two-dimensional electron energy-loss spectra resulting
from electron–molecule scattering within the models are briefly
discussed.